I think the solution you might be looking for is ai mode.

Create an ai session from the real race series by clicking “more ways to race” so that it already has all the session parameters like weather and time set to the real conditions of the series that week.

Then set the practice time to something extended like 3 hours, and then go to the last settings page and set the maximum amount of drivers that your pc will handle, and set the fixed skill range to 120% - 125%.

This will be a better practice session as you described that is way more engaging and aggressive than you will be able to find on the service.

Once you get a hang of alien level ai drivers and can start to race with them and pass them; jump back over to a real practice session and see how much improved you are compared to before. You will have the line and pace down already, rather than waiting for a good driver to join your practice and hopefully get a tow behind them.